Games of chance which do not have an element of skill typically include multiple possible game states and a random selection process that defines one of the game states as the winning outcome. For example, the game of craps uses two 6-sided dice that are rolled to yield 36 possible outcomes, American roulette uses a ball that is rolled into a spinning wheel where it comes to rest in one of 38 possible cups, and slot machines use multiple reels that each have numerous possible discrete stops, such as locations on the reel distinguished by symbols, that come to rest to reveal a particular combination (typically in the tens of thousands) of symbols.
The gaming industry is interested in new games, or modifications to existing games, which keep players interested and reduce the possibility that players will cease playing and wagering due to decreasing interest. One way that the excitement of wagering games can be enhanced is by increasing suspense in the outcome, which can be achieved by revealing the outcome over multiple random steps during a timeframe that is long enough for the player to appreciate the fluctuating probability of success as this probability increases and decreases during a round of play. Examples of games that increase suspense in the outcome include sports betting and card games, in which the likelihood of success changes as a round of play progresses. Craps, roulette, and slot machines lack this type of suspense because the outcomes are revealed relatively instantaneously as the dice, ball, and reels come to stop in a fraction of a second.
Games of chance that increase suspense in the outcome include the Galton box (also known as the quincunx or bean machine), which was invented by Sir Francis Galton in the 19th century to demonstrate the central limit theory. The Galton box consists of a vertical board with multiple interleaved rows of pegs, with a single row of bins across the bottom of the board. Balls are released from the top center of the board, and as a ball drops, the ball encounters a peg that causes the ball to bounce to the left and right with roughly equal probability, and proceeds to the next row of pegs, where the process repeats until the ball passes through the last rows of pegs to be collected into one-ball-wide bins at the bottom of the board. The height of the balls in the bins approximates a bell-shaped curve (such as the Normal probability distribution), thereby demonstrating the central limit theorem.
Modeled after the Galton box, Plinko is a game of chance that debuted on the television program “The Price is Right” on Jan. 3, 1983. A player drops a disc from the top of a vertical board with interleaved rows of pegs, and the disc eventually comes to a rest in one of the bins at the bottom of the board, to which various payout values have been assigned. The Plinko disc rattles side to side as it traverses the board, producing visual excitement and generating suspense in the outcome for each round of play. As the disc moves towards the bins with the higher payouts, the player becomes more excited as the probability of success increases, and as the disc moves away towards the bins with the lower payouts, the player becomes less excited as the probability of success decreases.